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81.
Genetic Resources and Crop Evolution - Blackgram [Vigna mungo (L.) Hepper] is a protein rich pulse crop of Indian origin. The crop is cultivated in diverse range of agro-ecological regions,...  相似文献   
82.
Plant Foods for Human Nutrition - Ficus geniculata (FG) is one of the underutilized fig species in India and throughout the world. However, the different parts of the plant have numerous...  相似文献   
83.

The meteorological drought dynamics and its impacts on rice productivity has been evaluated for the Indian Summer Monsoon Rainfall (ISMR) season using the standardized precipitation index (SPI) over the middle Gangetic plains (MGP) of Bihar. The meteorological drought over the ISMR period was found to be a recurring phenomenon coinciding with the rice growing season over Bihar. The rice crop has an intensive water requirement; therefore, it is significantly impacted by the meteorological droughts. In the present study, spatiotemporal characteristics viz. intensity, frequency, and probability of meteorological drought has been assessed along with an investigation for significant trends and detection of regime shift points to identify the impact of drought on rice production. For the purpose, SPI-4 derived from high resolution gridded daily rainfall data (0.25°?×?0.25°) from India Meteorological Department (IMD) has been considered to analyse the meteorological drought episodes over agro-climatic zones of Bihar from 1961 to 2019. The regime shifts were determined using the Rodionov test for the drought dynamics and production of rice in Bihar. A moderate to severe drought-prone zone was found over the zone BRZ3B; while zone BRZ2 and BRZ3A showed comparatively a greater number of mild drought events persisting with more than 70% probability of occurrence. An inkling of increasing dependency on groundwater is found, which is in turn governing the rice production regime. The present study shows there is a substantial need for climate resilience and food security policies incorporating the subtle linkage between SPI variability and crop production, especially over rice producing regions of the globe.

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84.
85.
Sex change in coral reef fish   总被引:1,自引:0,他引:1  
Gonadal differentiation can take many forms in fish, ranging from gonochorism, where individuals directly develop as male or female and finally possess only testis or ovaries at sexual maturation, to hermaphroditism where the same individuals can produce mature male and female gametes at some time in their lives. Hermaphrodite fish are, thus, an excellent model for studying the plasticity of sex determination and differentiation in vertebrates. We have shown that sex steroids play a principal role in sex differentiation and sex change in fish. Our laboratory implements several fish models that undergo sex change from female to male or male to female or in both directions. In this review, we will briefly discuss recent advances in our understanding of the mechanism of sex change in coral reef fish.  相似文献   
86.
This study examined the food organisms found in the gut of freshwater mussels, Lamellidens marginalis L. A total of 34 taxa of food organisms were recorded, out of which 30 taxa belonged to phytoplankton and four taxa to zooplankton. Both the groups comprised three families each: Cyanophyceae (blue‐green algae), Chlorophycea (green algae) and Bacillariophyceae (diatoms) constituted phytoplankton, whereas Euglenaceae, Chlamydodontidae and Brachionidae belonged to zooplankton. The total number of frequencies of phytoplankton (n=537) were almost nine times more than that of zooplankton (n=60). When blue‐green algae, green algae, diatoms and zooplankton (all the three families together) were tested for significant difference (P<0.05) following Duncan's multiple range test, the result showed only two groups. Blue‐green algae, green algae and zooplankton were not significantly different (P<0.05), forming group A, whereas diatoms were significantly different from others, forming group B. The present study showed that the maximum number of organisms that mussels feed upon belong to green algae, followed by diatoms, blue‐green algae and few taxa of zooplankton.  相似文献   
87.
Present research has delineated the biosorption potential of three different nonliving biomasses namely eucalyptus bark saw dust, mango bark saw dust, and pineapple fruit peel with respect to Zn (II) ion removal from liquid phase through batch experiments. The efficacy of Zn (II) ion biosorption onto surface of biosorbents was judged and correlated with biosorbent particle size, surface chemistry, and surface texture. Maximum metal ion uptake capacity, percentage removal, and minimum equilibrium concentration as 1.688 mg/g, 84.4%, and 1.56 mg/l, respectively, was obtained using eucalyptus bark saw dust mediated biosorption followed by mango bark saw dust as 1.028 mg/g, 51.4%, and 4.867 mg/l and pineapple fruit peel as 0.45 mg/g, 22.9%, and 7.71 mg/l, respectively, at a particle size of 0.5 mm. Additionally, present investigation also proved that biosorption efficiency and metal ion interaction with adsorbent surface also depends upon presence of functional groups involved in metal ion adsorption and surface porosity.  相似文献   
88.
This study was conducted with Aloe barbadensis in order to investigate the efficacy of four phosphate-solubilizing bacteria (PSB), Pseudomonas synxantha 10223, Burkholderia gladioli 10242, Enterobacter hormaechei 10240 and Serratia marcescens 10241 to solubilize Mussorie rock phosphate (MRP) and to evaluate its effects on growth, soluble P content and P uptake compared with control, i.e. uninoculated plants. Pot experiments were conducted in a greenhouse, in soil supplemented with MRP. Each PSB treatment showed different effects on different plant growth parameters. The maximum increase in leaf length (23.7%), total number of leaves (33.33%) and dry rind weight (69.10%) was observed in plants treated with P. synxantha 10223 compared with control. Whereas, maximum increase in root length (23.43%), fresh leaves weight (79.03%), dry gel weight (113.08%) and total gel volume (112.10%), was observed in plants treated with S. marcescens 10241 compared with uninoculated plants. Maximum increase in aloin-A content [114.92% (per g dry gel weight) and 322.32% (per plant dry gel weight)] was observed in plants treated with P. synxantha 10223 compared with control plants. Root colonization by inoculated PSB as estimated by RAPD technique showed that all PSB were able to survive in the rhizosphere of Aloe plants.  相似文献   
89.
Furrows are widely used in rainfed areas of semi-arid India for soil and water conservation. The orientation of furrows, either down or across slope, and their spacing influence the effectiveness of furrows as soil and water conservation measures. We evaluated treatments with furrows aligned down and across 3% sloping land at spacings of 90, 60 and 30 cm under simulated rainfall intensities of 80 and 100 mm/h on a shallow Alfisol. A bare plot without any furrows was considered as a control. A large (24 m × 3 m) rainfall simulator developed at the Central Research Institute for Dryland Agriculture (CRIDA), Hyderabad, was used for this controlled study. Run-off was measured by a calibrated tipping bucket run-off recorder. The effects of the treatments on peak flow rate (L/s), sediment loss with run-off water (kg/ha/mm), peak sediment concentration (g/L), run-off (per cent rainfall) and time to peak (min) were investigated. When compared with the control (no furrows), across slope furrowing with 60- and 30-cm spacing reduced sediment yields by 19.9 and 21.3 kg/ha/mm of run-off, respectively, under a rainfall intensity of 80 mm/h and 24 and 25.3 kg/ha/mm of run-off, respectively, under a rainfall intensity of 100 mm/h. For the control, sediment loss was 50.72 kg/ha/mm run-off and 56.68 kg/ha/mm run-off for rainfall intensities of 80 and 100 mm/h, respectively. Similar trends were recorded from observations of peak flow, time to peak and peak sediment concentration. Run-off hydrographs demonstrated the conservation value of across slope furrowing by delaying run-off initiation, reducing run-off and slowly releasing the run-off after the cessation of rainfall. The results show that furrow orientation has major effects on reducing run-off, whereas furrow spacing has insignificant effects.  相似文献   
90.
A number of field experiments were conducted at the Viswavidyalaya Research Farm during 1984–85 to 1986–87 to study the effects of five growth regulators viz. Miraculan (a triacontanol based growth stimulant), Nutron (1-triacontanol growth stimulant), Planofix ( α -napthylacetic acid), Paras or Mixtalol (Higher alcoholic carbon compounds) and N-triacontanol on productivity of five different major oilseed crops viz. rapeseed ( Brassica campestris L. var. yellow sarson), mustard ( Brassica juncea L. Czern and Coss), sesame ( Sesamum indicum L.), linseed ( Linum usitatissimum L.) and safflower ( Carthemus tinctorius L.). Results showed the positive influence of growth regulators on the productivity of crops (10–40 % increase in yield); however the influence was not consistent over the years. N-triacontanol when tried on mustard only improved the grain yield significantly, more so when applied with paras or planofix, sesame was most influenced by spraying planofix and paras. Nutron favourably influenced safflower and linseed. The test weight of grains followed by the number of pods/plant were influenced most by the application of growth regulators. Inconsistency in results over the years, however, need further investigations on the timing of spraying.  相似文献   
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